KALLAX Shelf unit, white, 30 1/8x30 1/8″
+12⅜″ margin
All items that fit an Aiways U5 2021
Will fit in an ?
No, it won't fit.
It will not fit in this setup: BILLY Bookcase, white, 31 1/2x11x79 1/2″ is too large for an Aiways U5 2021 with seats up.
Fit Details
With seats up, This package will not fit in this setup. The blocker is cargo length, and you're short by 20⅝″ even with diagonal loading. We're about 95% confident in this estimate.
BILLY Bookcase, white, 31 1/2x11x79 1/2″
Box: 81¼″ × 11¾″ × 5″ · 88 lb 1 oz
Based on IKEA US (United States).
Package dimensions last checked and updated on Oct 21, 2026
Also on IKEA:United Kingdom
Package
Status
Limiting factor
Best orientation
Package #1
81¼″ × 11¾″ × 5″
Status:20⅝″ short
Limited by
Limiting factor:Cargo length
Best orientation:Diagonal
Vehicle limits
Opening width / height above sill
39¾″ / 29⅛″
Cargo width / height
40⅛″ / 29⅞″
Cargo length seats up / down
41″ / 73¼″
Loading sill height
29⅞″
Aiways U5 2021
Measurements last checked and updated on Oct 21, 2026
Helpful tips
Use these loading tips to improve your chances of fitting BILLY Bookcase, white, 31 1/2x11x79 1/2″ in Aiways U5 2021.
Use available cargo length
Use seats down if available to gain cargo length.
Load diagonally first
Load diagonally first, then straighten once inside.
Try fitting alternatives
Check the Similar items that fit section for safer alternatives.
Alternatives that fit in Aiways U5 2021
Ranked by fit margin and package-dimension similarity. This improves as we index more items.
About the Aiways U5 2021 boot
Long flat packs suit the U5's boot. The floor runs 41″ with the rear seats up and 73¼″ with them folded, a gain of 32¼″. It is 40⅛″ wide at its narrowest, a little wider than the 39¾″ opening, so the opening sets the width limit. Above the loading sill there is 29⅛″ of clear height, enough to load a tall box upright. The harder part is the sill itself: it sits 29⅞″ off the ground, with the floor only ¾″ below. With a heavy box, ask a second person to take one end over the sill.
About the BILLY Bookcase, white, 31 1/2x11x79 1/2″ package
The white BILLY is packed in one long, narrow box: 81¼″ × 11¾″ × 5″. It weighs 88 lb 1 oz, and at that length you want a second person to carry it. Loaded end first, it asks little of the opening: only room for its 11¾″ by 5″ end. Lying flat and straight, it needs 81¼″ of floor for the longest side. On its side and at an angle, it needs less floor but more width at the opening, and the verdict on this page shows whether that works in your boot. Lift it level between the two of you and keep it that way until the whole box is in the boot.
Frequently asked questions
Find quick answers about fit for BILLY Bookcase, white, 31 1/2x11x79 1/2″ in Aiways U5 2021, including seats up vs seats down, limiting factor, best orientation, and package-by-package margins.
Will BILLY Bookcase, white, 31 1/2x11x79 1/2″ fit in Aiways U5 2021?
No. With seats up, it is short by 20⅝″ at Cargo length, even with diagonal loading.
What is the tightest part?
The limiting factor is Cargo length, with -20⅝″ margin in seats up.
Why does it not fit?
The blocker is Cargo length: with seats up, the box is 20⅝″ bigger than the space there.
Can I load it diagonally?
Yes, diagonal is the best orientation for this check, with -20⅝″ around the limiting point.
How tight is this fit?
This result is in the clear no-fit band (-20⅝″ at Cargo length).
Does it fit with seats up or seats down?
Seats up: No (-20⅝″). Seats down: No (-1½″). Default selection follows YES > MAYBE > NO.
What do YES, MAYBE and NO mean here?
YES means there is at least 2⅜″ to spare at the tightest point, in the best way the box can go in. MAYBE means it fits on paper, but with less than 2⅜″ to spare, so trim, the parcel shelf or the loading angle can decide it. NO means the box is bigger than the space at its tightest point, whichever way it goes in. Every margin on this page is that real gap: the car's measurement minus the box's.
What should I do instead?
Use the Helpful tips & alternatives section to choose a smaller item, different orientation, or split-load plan.
Which loading orientation works best?
Diagonal is the best orientation for this result in seats up.
How confident is this result?
Confidence is 95 out of 100 based on available dimensions and margin tightness.